The broadcasters would be able to perform said insertion in baseband (uncompressed format), provided that they are equipped with the same devices as the production studios. This solution is prohibitive in terms of cost, all the more since it is necessary to provide as many devices as broadcast modes (satellite, terrestrial, cable, ADSL, 4G, etc.). The result is that the broadcasters nominally insert said additional content in compressed format. Owing to this, the synchronization of the main and additional content is approximative, which has a great impact on quality of service.